This invention relates to a solid-fluid contacting apparatus and more especially to a solid-fluid contacting apparatus suitable for use in adsorption and desorption of fluid components by solid adsorbents and for flow type catalytic reactions and regeneration procedures.
There have thus far been proposed various diverse methods using a fixed bed, a fluidized bed or a moving bed for establishing contact between a solid and a fluid, in connection with adsorption, desorption, catalytic reaction and regeneration procedures, as well as corresponding apparatus for industrial application of these methods. Where two different operations such as adsorption and desorption or catalytic reaction and regeneration are required to be effected simultaneously or in parallel for continuous operation over a long time period, it has been the usual practice in the art to install a number of similar pieces of equipment in juxtaposition for alternate or sequential use or to use a separate apparatus for the process step of secondary nature or the step which takes a relatively short time (e.g., regeneration), and then returning the regenerated solid material to the main process. However, these methods invariably require apparatus of complicated construction as well as complicated operations, resulting in large increases in production and equipment costs.
On the other hand, more recently the quantities of fluids to be handled have increased considerably due to construction of large-scale chemical plants or large-sized printing and coating installations, necessitating provision of large solid-fluid contacting apparatus for use in adsorption or other chemical reaction processes. The conventional types of solid-fluid contacting apparatus have thus far been adapted to cope with the increases in the amount of fluid to be handled by increasing the diameters of the apparatus in order to increase the cross-sectional area for fluid flow or simply by increasing the number of pieces of apparatus. In any event, these countermeasures only contribute to an increase in required floor space or to an increase in the degree of complication of the equipment. The recent enforcement of severe regulations against air pollution, for example, also necessitates installation of large activated carbon adsorption apparatus in printing and coating shops to remove and collect by adsorption the organic solvents which are entrained in the exhaust gases. Manufacturers who have only limited space cannot comply with such requirements, since under the present circumstances this would unavoidably require a substantial enlargement in floor space.